A technology, in which two display panels overlap each other and an image is displayed on each display panel based on an input video signal, is conventionally proposed to improve contrast of a liquid crystal display device. Specifically, for example, a color image is displayed on a front-side (observer-side) display panel in two display panels disposed back and forth, and a monochrome image is displayed on a rear-side (backlight-side) display panel, thereby improving contrast.
In the liquid crystal display device described above, when pixels of the front-side display panel respectively deviate from corresponding pixels of the rear-side display panel, a desired image can hardly be displayed and display quality degrades.